In general, a storage case for keeping stored goods (for example, food) and a storage cover for opening and closing the opening of the storage case are airtightly coupled with each other to keep the stored goods contained in the storage case for a long time or to maintain the freshness of the stored goods.
Recently, various technologies of improving airtightness between the storage cover and the storage case when the storage cover and the storage case are coupled with each other are applied.
For example, like in the lock and lock (the name of a product), a technology of airtightly coupling the storage cover and the storage case with each other so that the airtightness between the storage cover and the storage case is maintained to keep the stored goods is applied.
In the case of the lock and lock and similar products, locking units for coupling the storage case and the storage cover with each other are provided.
The locking units are foldably provided on the sides of the storage cover and are coupled with and released from the coupling protrusions formed on the external rim of the storage case.
However, in the storage case and the storage cover that are coupled with and released from each other by the locking units, since the opening and closing operations of the storage cover coupled with and released from the storage case by operating the locking units (for example, the storage case is held by one hand and the storage cover is held by the other hand to perform opening and closing operations or, after one side of the storage cover is coupled with and released from the storage case, the same operation is repeated for several times in different parts to perform the opening and closing operations) are very complicated, it is inconvenient to use the storage case and the storage cover.
In addition, since the locking units integrated with the storage cover to be folded are torn by the folding operation repeated for several times or the gap between the storage case and the storage cover improves when the storage case and the storage cover are used for a long time, the airtightness between the storage case and the storage cover remarkably deteriorates in comparison with initial airtightness.
Furthermore, since the storage cover made of flexible rubber or synthetic resin is thin, the storage cover is easily transformed and twisted.
In addition, since the storage cover is vulnerable to heat (for example, the storage cover is transformed when the heat of no less than 50 is applied), it is not possible to heat the storage case and the storage cover to sterilize the storage case and the storage cover.